[Suicide Junkie]

-999% should still equal 1% minimum.

The chance of scoring no hits at all in a volley of 50 shots is (0.99^50) = 0.605 Therefore the chance of scoring one or more hits is 39.5%.

The Poisson distribution will quickly find the value for exactly 1 hit, the probability of two or more hits is equal to the probability of one or more hits, minus the probability of exactly one hit.
Recursively, that finds all the probabilities I quoted.